Human salivary samples contain calcium binding proteins with binding constants of two categories: weak or strong binding. The proteins with weak binding constants are thought to be functionally involved with the recalcification process of enamel while the strong binding proteins may actually be involved with the regulation of the secretory process or the maintenance of protein structure and function. It is proposed to isolate and characterize the calcium binding proteins with strong binding constants from human saliva. The calcium binding state in the human parotid and submandibular saliva may be a reflection of the clinical status. Patients with caries, cystic fibrosis and diabetes show abnormalities in their salivary calcium and in some cases, their calcium binding levels. This proposal is designed to study the relationship between the calcium binding proteins with strong constants and the clinical status of human salivary samples from heavy calculus formers, cystic fibrotics and diabetics over a three year period.